UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

FEB 0 4 Z013 

MEMORANDUM 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

SUBJECT: BEAD Chemical Profile for Registration Review: Abamectin (122804) 

FROM: 

THRU: 

TO: 

Don Atwood, Entomologist [t~ /JJ't, ~/ ~ Biological Analysis Branch 

Rafael A. Prieto, Environmental Protection Speciali;l}, 1M} t{ 

Science Information and Analysis Branch vvr; -' 

Derek Berwald, Economist 0 1 ~ ~ Economic Analysis Branch ~ W0. 

Biological and Economic Analysis Divisi n (7503 

Arnet Jones, Chief (} _o;J 

Biological Analysis Branch ~-, ( 

Diann Sims, Chief M,I'.£.41-A'-~.Y..~;;ttJ Science Information and Analysis Branch 

Economic 

Timothy Kiely, 

Analysis 

Chief 

Branch '-: 

~ ) \A,.. 

VV\,; 

~ 

Biological and Economic Analysts Division 503P) 

Khue Nguyen, Chemical Review Manager 

Risk Management and Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

Product Review Panel date: December 5, 2012 

INTRODUCTION 

The purpose ofthis document is to convey usage information and a broad overview of the pest 

management roles of pesticides that are beginning to undergo registration review. The 

anticipated audience consists of the team of EPA staff currently evaluating the registration status 

of abamectin and eventually the general public. This document builds upon the data already 

provided in the usage and label use data packages that are also provided to Registration Review 

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teams by BEAD. The document is based on information and data available to BEAD as of 

November 12, 2012. 

Abamectin is an insecticide/miticide/nematicide and was initially registered by the Agency in 

1986. Abamectin, also known as A vermectin B 1, is in the A vermectin chemical family 

(macrocylic lactones isolated from soil organism Streptomyces avermitilis) and is a natural 

fermentation product. Abamectin is a mixture containing more than 80% avermectin Bla (5-0-

dimethyl avermectin Ala) and less than 20% avermectin B1b (5-0-dimethyl-25-de(lmethylpropyl)-25-(1-methylethl) avermectin Ala). Abamectin is classified by the Insect 

Resistance Action Committee (IRAC) as a Group 6 insecticide, subgroup 

A vermectins/Milbemycins, impacting nerve and muscle action through chloride channel 

activation. The main target pests for abamectin include; nematodes (i.e. reniform and root knot), 

mites (i.e. 2 spotted spider, pacific spider, and citrus rust), asian citrus psyllid, leafminers, ants, 

silverfish, and cockroaches. 

COMMON FORMULATIONS AND APPLICATION METHODS 

Abamectin is formulated as granular, pelleted, tabletted, impregnated material, water dispersible 

granules, emulsifiable, flowable, soluble concentrate, solution-ready-to-use, and pressurized 

liquid and it is applied as aerial, banded, broadcast, ground, seed treatment, and spot treatment. 

USE SITES 

Agricultural Use Sites 

Abamectin is an insecticide registered for use on cotton, almond, oranges, pears, grapefruit, 

grapes, com, strawberries, tomatoes, lettuce, walnuts, apples, lemons, celery, avocados, spinach, 

peppers, cantaloupes, potatoes, plums/prunes, cucumbers, cherries, squash, peaches, pumpkins, 

onions, lima beans, apricots, beans (snap, bush, pole, string), alfalfa, pecans, and broccoli. 

Non-Agricultural Use Sites 

Abamectin is an insecticide registered for use on poultry houses, and agricultural premises, forest 

trees, herbaceous plants, ornamental plants, lawns and turf, woody shrubs and vines, domestic 

dwellings (private or commercial), recreational areas, commercial transportation facilities, food 

and feed processing plants, eating establishments, dairy cattle, and distribution facilities. 

USAGE 

Based on private market pesticide usage data from 2006-2011, abamectin' s annual agricultural 

usage averaged 57,000pounds of active ingredient (A. I.) treating an approximately 4 million 

acres, for an average application rate ofO.Ol pounds per acre. 

From 2006-2011, cotton (53%), almonds (18%), and oranges (8%) accounted for the largest 

percentages of usage in terms of total pounds of A. I. applied. For the same period of time cotton 

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(53%), almonds ( 18% ), and oranges ( 1 0%) accounted for the largest percentages of total area 

treated (TAT). This implies that the average application rate for cotton and almonds is similar to 

the overall average rate while the average application rate on oranges is somewhat less than the 

overall average. 

As seen on Table 1 below, the states with highest pounds (lbs.) applied and total area treated 

(TAT) for abamectin are California, Florida, Texas, and Georgia. The average application rate in 

Florida will be somewhat lower than the national average while rates in the other states will be 

similar to the national average. 

(Proprietary data, 2006-2011). 

USE TRENDS 

Agricultural 

Figure 1 depicts usage trends of abamectin, in terms of pounds A. I. applied, in the agricultural 

market. Abamectin usage remained constant from 1998 through 2005. Since 2005, there has 

been a steady increase in the usage of abamectin on surveyed agricultural crops. However, it 

should be pointed out that there has been a shift in the composition of primary crops being 

treated with abamectin from the earlier usage period (1998-2005) to current usage period (2006-

2011). Current usage trends for abamectin are illustrated in Figure 2. 

Fi ure 1. Total Pounds of Abamectin A s from 1998-2011 

120,000 

Lfl 

8 

....... 

Year 

Source: (Proprietary data, 1998-2011) 

3 
Fi ure 2. Pounds of Abamectin A 

60,000 

0 

2006 2007 2008 2009 

Year 

2010 2011 

• cotton 

• Almonds 

• oranges 

• Other 

"Other" refers to (in order of high to low average pounds applied): Pears, Grapefruit, Grapes, Com, 

Strawberries, Tomatoes, Lettuce, Walnuts, Apples, Lemons, Celery, Avocados, Spinach, Peppers, 

Cantaloupes, Potatoes, Plums/Prunes, Cucumbers, Cherries, Squash, Peaches, Pumpkins, Onions, Lima 

Beans, Apricots, Beans (Snap, Bush, Pole, String), Alfalfa, Pecans, and Broccoli. Source: (Proprietary 

data, 2006-2011) 

Agricultural Usage by Crop Reporting District 

Another measure of usage is the use intensity. In this analysis, the use intensity is expressed as 

the pounds a.i. applied per 1000 acres of land in farms. This differs from the application rate, 

which is expressed as the pounds a.i. applied per treated acres. The average application rate of 

0.01lb a.i. per acre implies a rate of 10 lb a.i. per 1000 acres. The maximum intensity observed 

is about 1.5 lb a.i. per 1000 acres of farmland. Figure 3 spatially represents abamectin's use 

intensity in the U.S., which is relatively greater in California and Florida. 

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Figure 3. Abamectin Usage by Crop Reporting District (2006- 2010) 

Average Pounds Per 

1,000 Acres of Farmland 

- <0.07 

0.07-0.22 

D o.23-o.45 

0.46- 0.78 

0.79- 1.5 

This is a map of agricultural pesticide usage at the Crop Reporting District (CRD) level prepared by BEAD 

for use in the Environmental Fate and Effects Division documents. These maps are used to help visualize 

where the pesticide being considered is most likely to be used and can be helpful in scenario selection and 

placing the exposure assessment in context. CRDs are boundaries created by USDA NASS which are 

aggregates of counties (USDA, 20 I 0). Pesticide usage is displayed as average pounds (for the years 2006-

2010) per 1,000 acres of farmland in a CRD to normalize for the variation in farmland between CRDs. 

Farmland acreage was obtained from USDA (2007). Farmland or "land in farms" is defined as follows: 

The acreage designated as "land in farms" consists primarily of agricultural land 

used for crops, pasture, or grazing. It also includes woodland and wasteland not 

actually under cultivation or used for pasture or grazing, provided it was part of 

the farm operator's total operation. Large acreages of woodland or wasteland 

held for nonagricultural purposes were deleted from individual reports during 

the edit process. Land in farms includes CRP, WRP, FWP, and CREP acres. 

Land in farms is an operating unit concept and includes land owned and 

operated as well as land rented from others. Land used rent free was reported as 

land rented from others. All grazing land, except land used under government 

permits on a per-head basis, was included as "land in farms" provided it was 

part of a farm or ranch. Land under the exclusive use of a grazing association 

was reported by the grazing association and included as land in farms. All land 

in American Indian reservations used for growing crops, grazing livestock, or 

the potential of grazing livestock was included as land in farms. Land in 

reservations not reported by reservation, individual American Indians or non5 
Native Americans was reported in the name of the cooperative group that used 

the land. In many instances, an entire American Indian reservation was reported 

as one farm (2007 Census of Agriculture, USDA). 

Usage is based on private market surveys ofpesticide use in agriculture (Proprietary Data, 2006-2010). The 

survey data are limited to the states that represent the top 80-90% of acreage for the individual crops, 

therefore, use may be occurring in regions outside the scope of the survey. CRDs showing no usage of 

pesticides may be due to either the lack of pesticide use in the region or non-participation in the agricultural 

surveys. In addition, across the years, there may be variations in the specific crops included in the CRD 

survey. This may result in a lower annual average for the CRD. 

This map displays ratio data (i.e., average pounds per I ,000 acres of farmland) summarized at a very highlevel. Readers are strongly cautioned against trying to over interpret the map without examination of the 

underlying data. The underlying data may explain some of the many reasons that a Crop Reporting District 

may have a high value for a particular active ingredient such as significant acreage (compared with the CRD 

as a whole) of a crop or crops with a high application rate and frequency of application. 

The reader should pay particular attention to the figure legends and realize that a map prepared for a 

particular chemical is not directly comparable to a map prepared for a different chemical. Scale and units of 

measurement do matter and may be different between maps. 

Sources: 

Proprietary Data. 2006-2010 

USDA, 2006-2010. NASS Crop Reporting Districts. Online: 

http://www.ers.usda.gov/briefing/arms/resourceregions/resourceregions.htm#nass. 

USDA, 2007. Census of Agriculture. Online: http://www.agcensus.usda.gov/Publications/2007/index.asp. 

Non-Agricultural Usage 

According to Kline (2006), approximately 2,000 pounds of abamectin were reported as being 

used in the household and houseplant consumer markets. The reported data shows that consumer 

use accounts for all of non-agricultural usage. It is important to note that this data is dated but is 

presented in this document for reference. 

BIOLOGICAL ASPECTS RELEVANT TO ABAMECTIN 

In addition, to considering the importance of an insecticide relative to the totallbs. applied, it is 

also important to consider insecticide use in terms of percent crop treated. In relation to percent 

crop treated, abamectin plays an important role in the production of major crops (greater than 

300,000 acres) and minor crops (less than 300,000 acres). Only one major crop, oranges, has 

greater that 20% crop acres treated with abamectin. In contrast, numerous minor crops have 

greater than 20% of crop acres treated with abamectin including; almonds, avocados, cantaloupe, 

celery, grapefruit, honeydew melon, lemons, pears, spinach, strawberries, tangelos, and 

tangerines. Due to the general reduced availability of registered insecticides for use on minor 

crops, abamectin has an important role in minor use crop production in the United States. 

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Foliar application of abamectin is safer on parasites and predacious mites of the target pests than 

some of the alternative insecticides. Therefore, abamectin is useful in development of IPM 

programs which incorporate biological control as a control strategy. The agricultural use of 

abamectin has expanded since 2006. This coincides with the registration of abamectin for use as 

a seed treatment in cotton. The rapid adoption of abamectin as a nematicide seed treatment on 

cotton reflected the uncertainty in the future availability of aldicarb. The Agency decided to 

cancel aldicarb and end production by December 31, 2014, end distribution and sale by 

December 31, 2016, and end use by August 31, 2018 (to allow growers to exhaust any remaining 

product). However, industry has since renewed aldicarb registration with the Agency. 

Therefore, any future expansion of abamectin use as a cotton nematicide will be dependent upon 

abamectin effectiveness and market competition with aldicarb. 

Abamectin is effective for use against non-agricultural pests (baits and gels) as it is a delayedaction insecticide and doesn't provide immediate insect death. The benefit of delayed-action 

insecticides as compared to those that kill instantly is that the poisoned insect is allowed time to 

travel back to the colony and spread the poison to other insects either through contact or food 

sharing (ingestion) 

HISTORY OF BEAD ASSESSMENTS FOR ABAMECTIN 

BEAD has not written a full benefit assessment for abamectin. BEAD has reviewed section 18 

requests for abamectin, including use for controlling thrips in onions because of resistance to 

other pesticides, and to control spider mites on lima beans, also due to resistance. 

INFORMATION THAT MAY BE USEFUL FOR BEAD'S FUTURE WORK ON 

ABAMECTIN 

Obtaining additional information on typical abamectin use in the non-agricultural sector would 

improve future BEAD assessments of the importance of abamectin and may be required as part 

of the registration review of this pesticide. Requested data should include, but not be limited to, 

application timing, application rate, application method, and application frequency. 

REFERENCES 

Kline & Co., 2006 

PMEP. 1994. Pesticide Information Profile - Abamectin. Pesticide Management Education 

Program - Cornell University Cooperative Extension. Available at: 

http:/ /pmep.cce.cornell.edu/profiles/ extoxnet/24d-captan/ abamectin-ext.html 

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Proprietary Data. 1998-2011 

Proprietary Data. 2006-2010 

USDA, 2006-2010. NASS Crop Reporting Districts. Online: 

http://www.ers.usda.gov/briefing/arms/resourceregions/resourceregions.htm#nass. 

USDA, 2007. Census of Agriculture. Online: 

http://www .agcensus. usda. gov /Publications/2007/index.asp. 

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